Control of liquid crystal alignment in an optical device

A method allowing simultaneous control of macroscopic azimuthal and zenithal liquid crystal (LC) alignment across a LC layer by controlling the area ratios between first, second and third different types of alignment region in a patterned alignment layer, the three different types of alignment region tending to induce LC alignment in the LC layer in three different respective, non-coplanar, principal orientations, wherein

• at least one of the types of alignment region has two choices of slightly different alignment to provide further control of macroscopic LC alignment, and
• the second type of alignment region has two such choices, with the two choices of the second type being used on opposite sides of an alignment region of the first type.

A method allowing simultaneous control of macroscopic azimuthal and zenithal liquid crystal (LC) alignment across a LC layer by controlling the area ratios between first, second and third different types of alignment region in a patterned alignment layer, the three different types of alignment region tending to induce LC alignment in the LC layer in three different respective, non-coplanar, principal orientations, wherein

• at least one of the area ratios between first, second and third different types of alignment region varies across the alignment layer, and
• the variation is controlled such that the macroscopic pattern of liquid crystal alignment across the LC layer presents a varying retardation for incident light of a particular linear polarisation.

A method allowing simultaneous control of macroscopic azimuthal and zenithal liquid crystal (LC) alignment across a LC layer by controlling the area ratios between first, second and third different types of alignment region in a patterned alignment layer, the three different types of alignment region tending to induce LC alignment in the LC layer in three different respective, non-coplanar, principal orientations, wherein a uniform macroscopic pattern of LC alignment is formed across the LC layer to form a birefringent optical element having its optic axis aligned at an angle to one of its surfaces so as to provide an image shifting function for light incident on that surface.

An optical device comprising a liquid crystal (LC) layer and at least one patterned alignment layer, the LC layer having a macroscopic pattern of azimuthal and zenithal LC alignment across the LC layer achieved using a method allowing simultaneous control of macroscopic azimuthal and zenithal liquid crystal (LC) alignment across a LC layer by controlling the area ratios between first, second and third different types of alignment region in the or each of the at least one patterned alignment layer, the three different types of alignment region tending to induce LC alignment in the LC layer in three different respective, non-coplanar, principal orientations, wherein the first type of alignment region tends to induce substantially homeotropic alignment and the second and third types of alignment region tend to induce substantially planar alignment in different respective principal orientations, and wherein control of macroscopic zenithal LC alignment is achieved by controlling the area ratios between the homeotropic and planar region types, and control of macroscopic azimuthal LC alignment is achieved by controlling the area ratio between the two planar region types.

A Graded Refractive Index, GRIN, lens comprising a liquid crystal (LC) layer and at least one patterned alignment layer, the LC layer having a macroscopic pattern of azimuthal and zenithal LC alignment across the LC layer achieved using a method allowing simultaneous control of macroscopic azimuthal and zenithal liquid crystal (LC) alignment across a LC layer by controlling the area ratios between first, second and third different types of alignment region in the or each of the at least one patterned alignment layer, the three different types of alignment region tending to induce LC alignment in the LC layer in three. different respective, non-coplanar, principal orientations, wherein at least one of the area ratios varies across the alignment layer such that the macroscopic pattern of liquid crystal alignment across the LC layer presents a varying retardation for incident light of at least one linear polarisation, and wherein the variation in retardation provides a lens function for light of the at least one polarisation.

An optical retarder comprising a liquid crystal (LC) layer and at least one patterned alignment layer, the LC layer having a macroscopic pattern of azimuthal and zenithal LC alignment across the LC layer achieved using a method allowing simultaneous control of macroscopic azimuthal and zenithal liquid crystal (LC) alignment across a LC layer by controlling the area ratios between first, second and third different types of alignment region in the or each of the at least one patterned alignment layer, the three different types of alignment region tending to induce LC alignment in the LC layer in three different respective, non-coplanar, principal orientations, wherein at least one of the area ratios varies across the alignment layer such that the macroscopic pattern of liquid crystal alignment across the LC layer presents a varying retardation for incident light of at least one linear polarisation.